1. Field
Example embodiments relate to X-ray pixels of flat panel X-ray detectors that directly detect double energy X-rays by using different photoconductors.
2. Description of the Related Art
A digital X-ray detector outputs an X-ray image and/or an X-ray penetration image captured by using an X-ray as a digital signal. The digital X-ray detector uses a direct method and/or an indirect method.
In the direct method, an X-ray is converted directly into electric charges by using, for example, a photoconductor. In the indirect method, an X-ray is converted into a visible ray by using, for example, a scintillator, and then the converted visible ray is further converted into electric charges by using a light conversion device such as a photodiode.
With regard to a flat panel X-ray detector, when an X-ray is emitted on/transmitted to/incident on each pixel of a pixel array, electrical charges are generated in a photoconductor, and the flat panel X-ray detector measures the amount of electrical charges generated so as to realize an image.
A medical image capturing apparatus distinguishes materials having different transmittance with respect to an X-ray in order to produce an image. Generally, the flat panel X-ray detector outputs a single signal with respect to each pixel.
However, a medical subject may include different materials. For example, cancer tissue and normal tissue, or hard tissue and soft tissue have excellent sensitivities with respect to different X-rays. Accordingly, when different X-rays are transmitted through different tissues, the different tissues may be accurately detected by the different X-rays, respectively. In such a manner, relatively higher quality images of the tissues may be obtained.